3.4 Density
Density and Temperature
  • the volume of most substances increases as the temperature increases however the temperature or volume will not alter the substance's mass.
  • density is the ratio of an objects mass to its volume.
  • generally, as the temperature increases the density decreases

Sample problem from page 91
Calculating dencity
A copper penny has a mass of 3.1 g and a volume of 0.35 cm^3. What is the density of copper?
1. ANALYZE-list the knowns and unknowns
Knowns: mass=3.1 g, volume =0.35 cm^3 Unknown: density =? g/cm^3
Use the known values and the following definition of density. Density= mass/volume
2. CALCULATE-solve for the unknown
substitute the known values and solve for density. Density=mass/volume=3.1g/0.35cm^3=8.8571g/cm^3
3. EVALUATE- Does the result make sense? the answer is yes

Nonmetals are in the upper right hand corner of the periodic table